Abstract: Method for characterization of polycyclic aromatic hydrocarbons (PAHs) by comprehensive two-dimensional gas chromatography (GC×GC) coupled with time-of-flight mass spectrometry (TOF MS) was established and applied in the detailed characterization of PAHs in heavy gas oil. Qualitative and semi-quantitative analyses of PAHs and alkyl substituted PAHs were carried out by the proposed method based on retention time, mass spectra and the NIST library of standard substances. Furthermore, the effects of structure and substituted alkyl on the hydrogenation of PAHs were investigated. Results show that the hydro-conversions of various PAHs are varied apparently due to their different structures, different sites and number of alkyl substitution. Owing to the high resolution power and enhanced sensitivity, GC×GC is a powerful tool to characterize target compounds in complex matrixes, and it will play an important role in the characterization of petroleum at molecular level.

Key words: comprehensive two-dimensional gas chromatography, time-of-Ffight mass spectrometry, heavy gas oil, polycyclic aromatic hydrocarbon